SICK: Workers yesterday investigate the Cleveland horror house (above) of Ariel Castro (below) — who used a mannequin to terrorize his family.AP

(Reuters)

SICK: Workers yesterday investigate the Cleveland horror house (left) of Ariel Castro (right) — who used a mannequin to terrorize his family. (
)

Long before the true extent of his crimes was known, Cleveland monster Ariel Castro terrorized his family by driving around with a freaky female mannequin in his car — dressing “her” up with a wig and jacket and using the prop to frighten his family.

Prior to abducting three women and brutalizing them for a decade, he kept the disturbing torso in the front passenger seat of his green Volvo, relatives said.

“It was creepy,” said Frank Caraballo, Castro’s former brother-in-law. “It was one of those mannequins that would be modeling a jacket in a store. He built it up by putting a jacket on it and a black wig.”

He used to torment his family with the dummy — once startling his then-wife, Grimilda Figueroa, so badly that she fell down a flight of stairs and hurt her head.

“He’d sneak up on people with it,” Caraballo said. “He scared my kids with it, and he snuck up on his wife and scared her, and that’s how she fell down the stairs.

“It was just funny to him, driving around with her,” he added.

Castro’s nephew — who grew up afraid of the man — said his uncle used to bully him with the weird dummy.

“He threatened me lots of times with it,” Angel Caraballo, 26, told The Associated Press. “He would say, ‘Act up again, you’ll be in that back room with the mannequin.’ ”

Meanwhile, new details emerged yesterday about Castro’s admissions to police. The rape fiend called himself “cold blooded,” WKYC reported.

Sources told the station that he seemed arrogant and was only sorry that he got caught.

The former school-bus driver wrote in a 2004 “suicide” note that he was a “sexual predator” and said he didn’t know why he continued to collect his prey.

“I don’t know why I kept looking for another,” he wrote in the self-pitying letter, according to local media. “I already had two in my possession.”

The letter also blamed his victims for agreeing to enter his car in the first place.

Castro’s Monday arrest ended a horrific decade for his trio of captives, whom he repeatedly raped, beat and bound over a decade in his decrepit, two-story home.

DNA testing proved yesterday that Castro is the biological father of a 6-year-old girl rescued from the home. Amanda Berry, 26, gave birth to the child, Jocelyn, in a kiddie pool in 2006, and fellow captive Michelle Knight delivered the infant. Castro threatened to kill Knight if the baby died.

Knight, meanwhile, left the hospital and is being cared for by fellow captive Gina DeJesus’ family — who may seek to adopt her, London’s Daily Mail reported.

Prosecutors may push for murder charges against Castro for allegedly forcing Knight to have at least five miscarriages by starving her and punching her in the stomach. He could face the death penalty.